Wireless telegraphy.



` UNITED YSTATES atented September 22, 1903.

PATENT OFFICE;

WIRELESS TELEG RAPHY.

SPECIFICATION forming part of Letters Patent No. 739,287, dated September 1903.

I Application filed April 11,1903. Serial No. 152,251. (No model.)v

To all whom it may concern:

Be it known that I, ELMER E.4 BUTOHER, a citizen of the United States, residing at North Ridgeville, in the county of Lorain and State of Ohio, have invented certain new and useful Improvements in Wireless Telegraphy 3' and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the letters of reference marked thereon, specification.

This invention relates to wireless telegraphy, and particularly to an automatic device for cutting in and out the aerial conductor and the receiving and transmitting apparatus. The action is automatic with the operation of the sending-key,and a particular object of the invention is to permit the operators at the respective stations to cut in on each other at will. vHeretofore it has been inconvenient or impossible for the operator at the receiving-station to stop or cut in on the operator at the transmitting-station when desired, as to have him correct a mistake in sending or to repeat, until he was done sending, because his receiver had to be disconnected while the transmitter was in operation.

The object of my invention is to remedy this by an arrangement which automatically connects the transmitter and disconnects the receiver with the aerial conductor each time the key is depressed and 'connects the receiver and disconnects the transmitter immediately the key lifts, thereby maintaining the receiver in circuit at all times except the instants when the transmitter is operating.

In the accompanying drawings, Figure lis a diagrammatic view of a stationwith the parts in receiving position, and Fig. 2 is a similar view in sending position. v

Referring particularly to the drawings, Athe sending-key is indicated at K5' the antennae at A; the ground connection at B; the induction-coil at X, the primary of which is connected with the batteryM; the oscillator or transmitter at O, and the coherer or receiver at D. s

At L is indicated the battery of a supplemental circuit, which operates electromagnets which form a part of thisl which control the automatic connection and disconnection of the receiver and transmitter according to the manipulation of the key K. One branch of this circuit contains the electromagnets E' for cutting out the receiver by separating the contacts F. The other branch contains the electromagnet H for cutting out the transmitter by separating the contacts N, and these branches are respectively connected to the contacts o and m on opposite sidesl of tact is indicated atiR in circuit and primary of the induction-coil. The contacts F are effected .under oil in vessels Gr in case the same antennze are used for transmitting and receiving. If 'different antennae are used, the connection need not be made under oil. The contacts 0 and R are so positioned with respect to the key that the former are connected,l when the key is depressed, before the latter. Norm ally the receiver is connected tothe antennae, the key K being normally lifted by the spring k, closing the contacts m. The current is then from the battery L through contacts m, electromagnet H, and

Vback to battery, the electromagnets E beingv out. The electromagnet H attracts its armature'h, which opens the contacts N and disconnects the transmitter from the antennae. VThe receiving-circuit in this position is from .the antennae A through contacts F F, coherer D, and to ground. Hence when the key is idle the coherer may receive signals.

Inv sending when the key is depressed it iirst breaks the contacts m and opens the circuit through H, permitting its armature to rise and close lthe contacts N, which puts the transmitter in circuit. rlhen it closes the contacts o and the circuit from the battery L through the electromagnets E, which attract their armatures e and open the contacts F, which disconnects the coherer D from the antennae and the earth. Further depression of the key closes the contact at R, which sends the key. The sending-conwith the key a current through the primary of the inducv tion-coil and sets up oscillations in the transmitter C, which are conducted to thel antennze. 1

It will be seen that just before the transmitting-circuit is closed the receiver is disconnected, but is reconnected and the transmitter disconnected just after the transmit- Amo ting-circuit is opened. In other Words, the key, in addition to its sending function, acts automatically, according` to its manipulation, to connect and disconnect the transmitter and receiver, respectively. Hence although the transmitter may be in operation the receiver will be in circuit during the intervals between the successive depressions of the key, and thus the operator at the receiving-station may at such intervals actuate the receiver at the sending-station, and thus stop or eut in on the operator there.

lVhat I claim `as new, and desire to secure by Letters Patent, is-

l. In a wireless-telegraph system, the combination with an aerial conductor, a receiver and a transmitter connected thereto, and means to operate the transmitter, of independent electrieally-operated switches actuated by said means, for alternately connecting,` and disconnecting the conductor with the receiver and transmitter respectively according to the sending` periods of the transmitter, substantially as described.

2. In a wireless-telegraph system, the combination with an aerial conductor, a receiver and a transmitter having' separate connections thereto, and contacts in said connections, of asending-key, and independent electric circuits actuated by the manipulation of the key to break either contact.

3. In a wireless-telegraph system, the com bination with a transmitter and a receiver, and an aerial conductor connected thereto, of electric circuits one of which has means to cut out the receiver from the conductor and the other of which has means to eut out the transmitter from the conductor, and a sending-key for the transmitter alternately opening and closing' said circuits respectively, in its manipulation.

4. In a wirelesswtelegraph system, the combination with a transmitter and a receiver, an aerial conductor having a separate con nection to each, and contacts in each of said connections, of electromagnets controlling said contacts, and a sending-key for the transmitter acting in its manipulation to alternately energize the magnets, substantially as described.

In testimony whereof I do affix my signature in presence of two witnesses.

ELMER E. BUTCHER.

Witnesses:

JOHN A. BoMMi-IARDT, Lo'rTIE NEWBURN. 

